Anode apparatus and methods regarding the same

ABSTRACT

In some embodiments, an anode apparatus comprises: (a) an anode body comprising at least one outer sidewall, wherein the outer sidewall is configured to define a shape of the anode body, and to perimetrically surround a hole in the anode body, wherein the hole comprises an upper opening in a top surface of the anode body and wherein the hole axially extends into the anode body; (b) a pin comprising: a first end and a second end opposite the first end, wherein the second end extends downward into the upper end of the anode body and into the hole of the anode body; and (c) a sealing material configured to cover at least a portion of at least one of the following: (1) an inner sidewall of the anode body; (2) the top surface of the anode body; (3) the pin; and (4) the anode support.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims benefit of U.S. provisional application No.62/396,583, filed Sep. 19, 2016, which is herein incorporated byreference in its entirety

BACKGROUND

An inert anode is electrically connected to the electrolytic cell, suchthat a conductor rod is connected to the inert anode in order to supplycurrent from a current supply to the inert anode, where the inert anodedirects current into the electrolytic bath to produce non-ferrous metal(where current exits the cell via a cathode). In some embodiments,during operation of the cell, corrosive bath and/or vapor interacts withthe anode assembly and can impact the effectiveness and longevity of theanode assembly (e.g. by weakening the mechanical connection, and/orincreasing resistivity at the electrical connection).

FIELD OF THE INVENTION

Generally, the instant disclosure is directed towards an inert anodeapparatus. More specifically, the instant disclosure is directed towardsan inert anode apparatus configured to reduce, prevent, and/or eliminatecorrosion of the pin and/or anode material (e.g. by corrosive vaporsand/or molten electrolyte) in an electrolysis cell.

SUMMARY OF THE DISCLOSURE

Without being bound by a particular mechanism or theory, it is believedthat one or more embodiments of the anode-pin-protective sealingmaterial connection in the instant disclosure provide enhanced corrosionresistance to the anode assembly when measured in at least one of thefollowing locations: (a) at the pin, inside the hole in the anode body;(b) at the anode body, along the inner diameter of the hole for theanode pin; and/or (c) in the vapor zone where the pin extends above theanode body (i.e., above the bath, and/or in the refractory package).

Without being bound by a particular mechanism or theory, it is believedthat when the sealing material is utilized in the anode assembly, itprovides protection to (1) mechanical attachment site of the anode topin and/or (2) the anode assembly components (e.g. pin, anode body,filler material, cement material) as the sealing material is configuredto accept reactive fluoride species that are present in situ in the bathand/or bath vapor. Without being bound by a particular mechanism ortheory, it is believed that by undergoing the chemical transformation toaccept the fluoride species, the sealing material is transformed (atleast partially) from a solid to a liquid material. In some embodiments,a sealing material is configured to extend between the inner surface ofthe hole in the anode body and the outer diameter of the pin.

In one aspect of the instant disclosure, an anode assembly is provided,comprising: an anode support; and an anode apparatus mechanicallyattached to the anode support, wherein the anode apparatus comprises:(a) an anode body comprising at least one outer sidewall, wherein theouter sidewall is configured to define a shape of the anode body, and toperimetrically surround a hole in the anode body, wherein the holecomprises an upper opening in a top surface of the anode body andwherein the hole axially extends into the anode body; (b) a pincomprising: a first end connected to a current supply, and a second endopposite the first end, wherein the second end extends downward into theupper end of the anode body and into the hole of the anode body; and (c)a sealing material comprising an aggregate and a matrix, wherein thesealing material is configured to cover at least a portion of at leastone of the following: (1) an inner sidewall of the anode body; (2) thetop surface of the anode body; (3) the pin; and (4) the anode support.

In some embodiments of the instant disclosure, the sealing materialcomprises at least one of: water, polymers, organics, dispersants, ordiluents.

In some embodiments of the instant disclosure, a sealing material isconfigured to cover at least a portion of at least one of the following:(1) an inner sidewall of the anode body; (2) the pin; and (3) a fillermaterial.

In some embodiments of the instant disclosure, the first end of the pinis configured to be retained within an anode support.

In some embodiments of the instant disclosure, the filler is retained inthe hole between the inner sidewall of the anode body and the pin.

In some embodiments of the instant disclosure, the sealing material isconfigured to enclose the conductive filler into the anode body betweenthe inner sidewall of the anode body and the pin.

In some embodiments of the instant disclosure, the sealing material iscast in place.

In some embodiments of the instant disclosure, the sealing material ispre-cast and screwed into the anode body.

In some embodiments of the instant disclosure, the sealing material issintered into place during the sintering of the green form anode bodyinto the final anode body.

In some embodiments of the instant disclosure, the sealing material isretained above the top surface of the anode body.

In some embodiments of the instant disclosure, the sealing material isretained in the hole.

In some embodiments of the instant disclosure, above the top surface ofthe anode body includes extending along the pin.

In some embodiments of the instant disclosure, above the top surface ofthe anode body includes extending along the pin and into the anodesupport.

In some embodiments of the instant disclosure, above the top surfaceincludes extending across the top surface of the upper portion of theanode body.

In some embodiments of the instant disclosure, above the top surfaceincludes extending across the top surface and extending down around theouter sidewall of the anode body.

In some embodiments of the instant disclosure, the sealing material isapplied to the anode hole between the pin and the inner surface of theanode body in a gradient, such that the concentration of sealingmaterial varies in a radial direction.

In some embodiments of the instant disclosure, the gradient isconfigured such that the concentration of sealing material is higheradjacent to the pin as compared to adjacent to the inner surface of theanode body.

In some embodiments of the instant disclosure, the gradient isconfigured such that the concentration of sealing material is loweradjacent to the pin as compared to adjacent to the inner surface of theanode body.

In some embodiments of the instant disclosure, the sealing material isapplied to the anode hole between the pin and the inner surface of theanode body in a gradient, such that the concentration of sealingmaterial varies in a lateral direction.

In some embodiments of the instant disclosure, the gradient isconfigured such that the concentration of sealing material is higheradjacent to the upper end as compared to adjacent to the lower end ofthe anode body.

In some embodiments of the instant disclosure, the gradient isconfigured such that the concentration of sealing material is loweradjacent to the upper end as compared to adjacent to the lower end ofthe anode body.

In some embodiments of the instant disclosure, the sealing material isconfigured with a higher concentration at a position adjacent to thebath-vapor interface, as compared to either the upper end in the vaporphase or the lower end in the bath of the anode body.

In some embodiments of the instant disclosure, the concentration ofsealing material from a position just below the bath-vapor interface toa position adjacent to the upper end of the anode is higher than theportion of sealing material in the submerged portion of the anode body.

In one aspect of the instant disclosure, an electrolysis cell,comprising: a cell structure comprising a cell bottom and a cellsidewall, wherein the cell sidewall is configured to perimetricallysurround the cell bottom and extend in an upward direction from the cellbottom to define a control volume, wherein the control volume isconfigured to retain a molten electrolyte bath; and an anode assemblyconfigured to direct current into the molten electrolyte bath, whereinthe anode assembly comprises: an anode support; and an anode apparatusmechanically attached to the anode support, wherein the anode apparatuscomprises: (a) an anode body comprising at least one outer sidewall,wherein the outer sidewall is configured to define the anode shape andto perimetrically surround a hole in the anode body, wherein the holecomprises an upper opening in the top of the anode body and wherein thehole axially extends into the anode body; and (b) an pin comprising: afirst end connected to a current supply, and a second end opposite thefirst end, wherein the second end is configured to extend down into theupper end of the anode body and into the hole of the anode body; and (c)a sealing material configured to cover at least a portion of at leastone of the following: an inner sidewall of the anode body; the topsurface of the anode body; the pin; and the anode support.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention, briefly summarized above anddiscussed in greater detail below, can be understood by reference to theillustrative embodiments of the invention depicted in the appendeddrawings. It is to be noted, however, that the appended drawingsillustrate only typical embodiments of this invention and are thereforenot to be considered limiting of its scope, for the invention may admitto other equally effective embodiments.

FIG. 1 depicts a block diagram of a generic anode assembly in accordancean embodiment of the instant disclosure.

FIG. 2 depicts a schematic cut-away side view of an anode apparatus inaccordance with an embodiment of the instant disclosure.

FIG. 3 depicts a cut-away side view of an embodiment of an anodeapparatus of the instant disclosure.

FIG. 4 depicts a cut-away side view of an embodiment of an anodeapparatus of the instant disclosure.

FIG. 5 depicts a cut-away side view of an embodiment of an anodeapparatus of the instant disclosure.

FIG. 6 depicts a cut-away side view of an embodiment of an anodeapparatus of the instant disclosure.

FIG. 7 depicts a cut-away side view of an embodiment of an anodeapparatus of the instant disclosure.

FIG. 8 depicts a cut-away side view of an embodiment of an anodeapparatus of the instant disclosure.

FIG. 9 depicts a cut-away side view of an embodiment of an anodeapparatus of the instant disclosure.

FIG. 10 depicts a cut-away side view of an embodiment of an anodeapparatus of the instant disclosure.

FIG. 11 depicts a cut-away side view of an embodiment of an anodeapparatus of the instant disclosure.

FIG. 12 depicts a cut-away side view of an embodiment of an anodeapparatus of the instant disclosure.

FIG. 13 depicts a cut-away side view of an embodiment of an anodeapparatus of the instant disclosure.

FIG. 14 depicts a cut-away side view of an embodiment of an anodeapparatus of the instant disclosure.

FIG. 15 depicts a cut-away side view of an embodiment of an anodeapparatus of the instant disclosure.

To facilitate understanding, identical reference numerals have beenused, where possible, to designate identical elements that are common tothe figures. The figures are not drawn to scale and may be simplifiedfor clarity. It is contemplated that elements and features of oneembodiment may be beneficially incorporated in other embodiments withoutfurther recitation.

DETAILED DESCRIPTION

FIG. 1 depicts a block diagram of a generic anode assembly 10 inaccordance an embodiment of the instant disclosure. In some embodimentsof the instant disclosure, the anode assembly 10 comprises an anodesupport and an anode apparatus. In some embodiments, the anode apparatusis mechanically attached to the anode support (e.g. refractory package,structural support member, combination thereof). In some embodiments,the anode apparatus comprises: an anode body, a pin, and a sealingmaterial.

In some embodiments, the anode assembly is a part of an electrolysiscell comprising a cell structure comprising a cell bottom and a cellsidewall. In some embodiments, the cell sidewall is configured toperimetrically surround the cell bottom and extend in an upwarddirection from the cell bottom to define a control volume. In someembodiments, the control volume is configured to retain a moltenelectrolyte bath.

In some embodiments, the anode body comprises at least one outersidewall. In some embodiments, the outer sidewall is configured todefine a shape of the anode body and to perimetrically surround a holein the anode body. In some embodiments, the hole comprises an upperopening in a top surface of the anode body and the hole axially extendsinto the anode body. In some embodiments, the pin comprises a first endand a second end. In some embodiments, the first end is connected to acurrent supply. In some embodiments, the second end is opposite thefirst end. In some embodiments, the second end extends downward into theupper end of the anode body and into the hole of the anode body.

In some embodiments, the sealing material is configured to cover atleast a portion of at least one of the following: an inner sidewall ofthe anode body; the top surface of the anode body; the pin; and theanode support. In some embodiments, the sealing material is configuredto cover at least a portion of at least one of the following: an innersidewall of the anode body; the pin; and a filler material.

In some embodiments, the sealing material is configured to reduce,prevent, or eliminate corrosive constituents of the electrolysis processfrom contacting (and corroding) (1) the pin and/or (2) the mechanicalattachment site of the anode body to the pin. In some embodiments, thesealing material is configured to be tailored (i.e. matched) to thecomposition of the anode body. In some embodiments, the sealing materialis configured such that aggregate present in the sealing material iscompositionally consistent with the anode body composition. In someembodiments, the sealing material is configured to substantially overlapwith the coefficient of thermal expansion of the anode body.

In some embodiments, the sealing material is inserted into the anodebody (between the inside of the anode body and the pin) as a particulatematerial. In some embodiments, the sealing material is inserted into theanode body (between the inside of the anode body and the pin) as aliquid/slurry applied to the anode body or pin. In some embodiments,when the sealing material is inserted into/added onto the anode body, itundergoes a chemical and/or thermal cure in order to form a solidsealing material. In some embodiments, the sealing material ispositioned between the pin and the anode body.

In some embodiments, a sealing material is utilized around the upper endof the anode body, surrounding the outer surface of the pin andcontacting the anode body (e.g. inner portion of the hole in the anodebody, top surface of the anode body, upper portion of the anode body,and/or combinations thereof). In some embodiments, the sealing materialcomprises a cement. In some embodiments, the sealing material comprisesa grout. In some embodiments, the sealing material is configured toprevent corrosive vapors from entering into the inner surface of theanode body, proximal to the portion of the pin that is retained withinthe anode body.

In some embodiments cement includes aggregate and a binder or matrix. Insome embodiments, the aggregate is replaced with a sealing material inaccordance with the instant disclosure (e.g. utilizing the commerciallyavailable binder and/or matrix). In some embodiments, the matrix orbinder is replaced with a sealing material in accordance with theinstant disclosure (e.g. utilizing the commercially availableaggregate). In some embodiments, the matrix or binder and aggregate isreplaced with a sealing material in accordance with the instantdisclosure. Some non-limiting commercial examples of binders, matrices,aggregates, and/or combinations thereof include: Al₂O₃, SiO₂, MgO, CaO,or the like.

In some embodiments, the sealing material includes at least one of:water, polymers, organics, dispersants, and/or diluents in order topromote a flowable sealing material such that the sealing material isformable/flowable into its desired location (e.g. in the anode assemblyand/or anode body).

In some embodiments, the sealing material is configured to enclose theconductive filler into the anode body (i.e. between the inner sidewallof the anode body and the pin). In some embodiments, the sealingmaterial is configured to provide a mechanical attachment of the anodebody to the pin. In some embodiments, the sealing material is configuredto provide structural support to the anode assembly and/or anodeapparatus.

In some embodiments, the sealing material is cast in place. In someembodiments, an accelerant is utilized in combination with the sealingmaterial in order to reduce the curing time. In some embodiments, thesealing material is pre-cast and screwed into the anode body (e.g. upperportion of the anode body). In some embodiments, the sealing material issintered into place while/during the sintering of the green form anodebody into the final anode body/anode assembly (anode body, pin, andsealing material). In some embodiments, the sealing material is retainedabove the hole, proximal to the top surface of the upper end of theanode. In some embodiments, sealing material is retained in the hole(i.e. extending between the pin and the inner sidewall of the anodebody) and above the top surface of the anode body.

In some embodiments, above the top surface of the anode body includesextending along the pin (i.e. portion of the pin that extends out of theanode body). In some embodiments, above the top surface of the anodebody includes extending along the pin and into the anode support (i.e.portion of the pin that extends into the anode support, where the pin ismechanically attached). In some embodiments, above the top surfaceincludes extending across the top surface of the upper portion of theanode body. In some embodiments, above the top surface includesextending across the top surface and extending down around the outersidewall of the anode body (i.e. creating a collar around the upper endof the anode surface).

As used herein, “anode” means the positive electrode (or terminal) bywhich current enters an electrolytic cell. In some embodiments, theanodes (i.e. anode bodies) are constructed of electrically conductivematerials. In some embodiments, the anode comprises an inert anode (e.g.non-reactive, dimensionally stable, and/or having a dissolution rate(e.g. at the cell operating parameters) less than that of acorresponding carbon anode).

As used herein, “anode body” means: the physical structure of the anode(e.g. including the top, bottom, and sidewall(s)). Some non-limitingexamples of anode materials include: metals, metal alloys, metal oxides,ceramics, cermets, and combinations thereof. In some embodiments, theanode body is oval, cylindrical, rectangular, square, plate-shaped(generally planar), other geometrical shapes (e.g. triangular,pentagonal, hexagonal, and the like

As used herein, “anode apparatus” means the anode or positive electrodein the electrolysis cell. In some embodiments, the anode apparatusincludes: the anode body and anode pin. In some embodiments, the anodeapparatus includes the anode body, anode pin, and filler/sealingmaterials (e.g. individually, or in combination: conductive fillerand/or sealing material).

As used herein, “anode assembly” means at least one anode apparatus(anode body, pin, conductive filler, and/or sealing material) and ananode support, where the at least one anode apparatus is connected (e.g.mechanically and/or electrically) to the anode support.

As used herein, “support” means a member that maintains anotherobject(s) in place. In some embodiments, the support is the structurethat retains the anode(s) in place. In one embodiment, the supportfacilitates the electrical connection of the electrical bus work to theanode(s). In one embodiment, the support is constructed of a materialthat is resistant to attack from the corrosive bath. For example, thesupport is constructed of insulating material, including, for examplerefractory material. In some embodiments, multiple anodes are connected(e.g. mechanically and electrically) to the support (e.g. removablyattached), which is adjustable and can be raised, lowered, or otherwisemoved in the cell. In some embodiments, the anode support includes arefractory material (e.g. block or assembly), other bath resistantmaterials, rail or beam support members, vertical adjustment componentsand apparatuses, and/or electrical bus work.

As used herein, “electrical bus work” refers to the electricalconnectors of one or more component. For example, the anode, cathode,and/or other cell components can have electrical bus work to connect thecomponents together. In some embodiments, the electrical bus workincludes pin connectors in the anodes, the wiring to connect the anodesand/or cathodes, electrical circuits for (or between) various cellcomponents, and combinations thereof.

As used herein, “sidewall” means: a surface that forms the wall of anobject.

As used herein, “perimetrically surrounding” means: surrounding theoutside edge of a surface. As a non-limiting example, perimetricallysurrounding includes different geometries (e.g. concentricallysurrounding, circumscribing) and the like.

As used herein, “electrolyte bath” (sometimes interchangeably referredto as bath) refers to a liquefied bath having at least one species ofmetal to be reduced (e.g. via an electrolysis process). A non-limitingexample of the electrolytic bath composition (in an aluminumelectrolysis cell) includes: NaF—AlF₃, NaF, AlF₃, CaF₂, MgF₂, LiF, KF,and combinations thereof—with dissolved alumina.

As used herein, “molten” means in a flowable form (e.g. liquid) throughthe application of heat. As a non-limiting example, the electrolyticbath is in molten form (e.g. at least about 750° C.). As anotherexample, the metal product that forms at the bottom of the cell (e.g.sometimes called a “metal pad”) is in molten form.

In some embodiments, the molten electrolyte bath/cell operatingtemperature is: at least about 750° C.; at least about 800° C.; at leastabout 850° C.; at least about 900° C.; at least about 950° C.; or atleast about 975° C. In some embodiments, the molten electrolytebath/cell operating temperature is: not greater than about 750° C.; notgreater than about 800° C.; not greater than about 850° C.; not greaterthan about 900° C.; not greater than about 950° C.; or not greater thanabout 975° C.

As used herein, “vapor” means: a substance that is in the form of a gas.In some embodiments, vapor comprises ambient gas mixed with causticand/or corrosive exhaust from the electrolysis process.

As used herein, “vapor space” refers to the head space in anelectrolysis cell, above the surface of the electrolyte bath.

As used herein, “interface” refers to a surface regarded as the commonboundary of two bodies, spaces, or phases.

As used herein, “bath-vapor interface” refers to the surface of bath,which is the boundary of two phases, the vapor space and the liquid(molten) electrolyte bath.

As used herein, “metal product” means the product which is produced byelectrolysis. In one embodiment, the metal product forms at the bottomof an electrolysis cell as a metal pad. Some non-limiting examples ofmetal products include: aluminum, nickel, magnesium, copper, zinc, andrare earth metals.

As used herein, “at least” means greater than or equal to.

As used herein, “hole” means: an opening into something.

As used herein, “pin” means: a piece of material used to attach thingstogether. In some embodiments, the pin is an electrically conductivematerial. In some embodiments, the pin is configured to electricallyconnect the anode body to the electrical buswork in order to providecurrent to an electrolysis cell (via the anode). In some embodiments, afirst end of the pin is configured to fit into/be retained within ananode support (e.g. anode support and at least one anode apparatus is ananode assembly) In some embodiments, the pin is configured to overlapwith the anode body. In some embodiments, the pin is configured tostructurally support the anode body, as it is attached to and suspendedfrom the pin. In some embodiments, the pin is stainless steel, nickel,nickel alloy, Inconel, or a corrosion protected steel. In someembodiments, the pin is configured to extend into the anode body (e.g.into a hole) to a certain depth, in order to provide mechanical supportand electrical communication to the anode body. In some embodiments, thelength of the pin is sufficient (long enough) to provide mechanicalsupport to the anode body and sufficient to (short enough) to preventcorrosion on the pin inside the hole (i.e. locate the pin above thebath-vapor interface) In some embodiments, the pin is oval, cylindrical,rectangular, square, plate-shaped (generally planar), other geometricalshapes (e.g. triangular, pentagonal, hexagonal, and the like).

As used herein, “attach” means: to connect two or more things together.In some embodiments, the pin is attached to the anode body. In someembodiments, the pin is mechanically attached to the anode body by:fastener(s), screw(s), a threaded configuration (e.g. on pin), a matingthreaded configuration (e.g. on inner surface of hole in anode body andon pin), or the like. In some embodiments, the pin is attached to theanode body via welding (e.g. resistance welding or other types ofwelding). In some embodiments, the pin is attached to the anode body viaa direct sinter (i.e. sintering the anode body onto the pin directly).

As used herein, “electrically conductive material” means: a materialthat has an ability to move electricity (or heat) from one place toanother.

As used herein, “filler” means: a material that fills a space or voidbetween two other objects. In some embodiments, the filler is configuredto connect (e.g., electrically connect) the anode body to the pin. Insome embodiments, non-limiting examples of filler include: a particulatematerial, a liquid/slurry material, and combinations thereof. In someembodiments, the filler is incorporated/inserted into the desiredlocation in a flowable form, which then hardens over time to yield asolid filler material.

In some embodiments, the filler is a conductive material, also referredto as conductive filler. In some embodiments, the filler is configuredto electrically connect the pin to the anode body. Non-limiting examplesof electrically conductive filler materials include: iron oxides(hematite, magnetite, wustite), copper, copper alloys, nickel, nickelalloys, precious metals, (e.g., Pt, Pd, Ag, Au) and combinationsthereof.

As used herein, “sealing material” means: a substance used to close orsecure an object or component (e.g. in order to reduce, prevent, and/oreliminate the transmittal of vapor or liquid to the object orcomponent). In some embodiments, the filler is configured to seal theupper portion hole in the anode body from corrosive vapors present inthe vapor space. Non-limiting examples of a sealing material include:castable cement, concrete, grout, mortar, and combinations thereof.

In some embodiments, the sealing material is a substance/material thatincludes at least two components: (1) aggregate and (2) matrix cement(e.g., grout), where the aggregate includes large and/or fine aggregatesizes. In some embodiments, the sealing material is applied to an areain order to act as an adhesive, as it is configured to adhere componentstogether upon hardening.

As used herein, “castable” means: a substance/material that includes atleast two components: aggregate and cement, where the aggregate includeslarge and fine aggregate sizes. In some embodiments, the castable isapplied to an area such in order to act as an adhesive, as it isconfigured to adhere components together upon hardening.

As used herein, “grout” means: a castable with matrix and fineraggregate (as compared to concrete or cement). In some embodiments, thegrout includes a viscosity configured to fill cracks and crevices in theanode assembly and/or anode apparatus. In some embodiments, the grout isconfigured as a bonding material that hardens in place and is used tobind things together.

As used herein, “particulate material” means: a material composed ofparticles. In some embodiments, the particulate material is electricallyconductive. In one embodiment, the particulate material is copper shot.Other non-limiting examples of particulate materials include: preciousmetals (e.g. platinum, palladium, gold, silver, and combinationsthereof). As non-limiting examples, the particulate material includes:metal foam (e.g. Cu foam), large or small shot (e.g., configured to fitbetween the pin and the anode body and/or in the anode hole), paint,and/or powder. Other sizes and shapes of particulate materials areutilizable, provided they fill the void between the pin and the anodebody (or portion below the pin, in the hole of the anode body) andpromote an electrical connection between the anode body and the pin toprovide current to the anode.

In some embodiments, the sealing material is configured to reduce,prevent, or eliminate corrosion from the anode apparatus (e.g. pin,anode body, conductive filler, and/or combinations thereof).

In some embodiments, the sealing material includes aggregate that isconfigured as an anode-matched aggregate. In some embodiments, thesealing material is configured as an off-gas compatible aggregate (e.g.,configured to react but not substantially degrade the effectiveness ofthe sealing material.

As used herein, “anode-matched aggregate” (sometimes referred to as offgas compatible aggregate) means aggregate that has an overlappingperformance characteristics as the anode composition. In someembodiments, anode matched aggregate is aggregate having the samecompositional constituent as the anode body (e.g. hematite, magnetite).In some embodiments, anode matched aggregate is aggregate having acomposition that is consistent with at least one major species (orcompound) present in the anode (e.g. >30 wt. %). In some embodiments,anode matched aggregate is aggregate having a compound or component ofan off-gas compatible aggregate (e.g. NiFe₂O₄, NiO, CuAl₂O₄, CuO). Somenon-limiting examples of aggregating sealing materials include: spinels,magnetite, hematite, copper aluminate, nickel ferrite, or tin oxide, andcombinations thereof.

In some embodiments, the sealing material comprises a castable ceramicor cermet plug, where the aggregates (or at least a portion thereof) arereplaced with an anode-matched aggregate and/or an off-gas compatibleaggregate as the primary seal. As a non-limiting example, the sealingmaterial comprises a castable ceramic or cermet containing Al₂O₃, SiO₂,MgO, CaO, Na₂O, and combinations thereof, where at least some of thesilicates and/or aluminates are replaced with an aggregate specificallytailored/matched to the anode body and/or pin material, in accordancewith the instant disclosure.

In some embodiments, the aggregate is about 40 wt. % of the sealingmaterial (e.g. as cured). In some embodiments, the matrix/binder isabout 60 wt. % of the sealing material (e.g. as cured). In someembodiments, the aggregate is from about 5 wt. % to 100 wt. % of thesealing material. In some embodiments, the binder/matrix is from about 5wt. % to 100 wt. % of the sealing material.

In some embodiments, the percentage and/or quantity of aggregate orbinder/matrix is quantified via SEM (scanning electron microscope) orEDS (energy dispersive spectroscopy), via viewing/observing a polishedcross-section of sealing material. In this embodiment, EDS is configuredto provide the chemical make-up of the cross-section.

In some embodiments, the filler is conductive filler (e.g. configured topromote electrical communication between the pin and the anode body).

In some embodiments, within the hole, where the filler is configured toextend between the inner sidewall of the anode body and the pin (e.g.beneath the sealing material).

In some embodiments, the sealing material comprises a thickness of: from1 mm to not greater than 50 mm.

In some embodiments, the sealing material has a thickness of: at least 1mm; at least 2 mm; at least 3 mm; at least 4 mm; at least 5 mm; at least6 mm; at least 7 mm; at least 8 mm; at least 9 mm; or at least 10 mm.

In some embodiments, the sealing material has a thickness of: at leastabout 5 mm; at least about 10 mm; at least about 15 mm; at least about20 mm; at least about 25 mm; at least about 30 mm; at least about 35 mm;at least about 40 mm; at least about 45 mm; or at least about 50 mm.

In some embodiments, the sealing material has a thickness of: notgreater than 1 mm; not greater than 2 mm; not greater than 3 mm; notgreater than 4 mm; not greater than 5 mm; not greater than 6 mm; notgreater than 7 mm; not greater than 8 mm; not greater than 9 mm; or notgreater than 10 mm.

In some embodiments, the sealing material has a thickness of: notgreater than about 5 mm; not greater than about 10 mm; not greater thanabout 15 mm; not greater than about 20 mm; not greater than about 25 mm;not greater than about 30 mm; not greater than about 35 mm; not greaterthan about 40 mm; not greater than about 45 mm; or not greater thanabout 50 mm.

In some embodiments, the sealing material has a thickness of: at leastabout 50 mm; at least about 100 mm; at least about 150 mm; at leastabout 200 mm; or at least about 250 mm. In some embodiments, the sealingmaterial has a thickness of: not greater than about 50 mm; not greaterthan about 100 mm; not greater than about 150 mm; not greater than about200 mm; or not greater than about 250 mm.

In some embodiments, the sealing material is configured as a coatingapplied to the anode pin. In some embodiments, the sealing material isconfigured as a coating to the inner surface of the anode body. In someembodiments, the sealing material is configured as a coating applied tothe upper surface (e.g. top end) of the anode body.

In some embodiments, the sealing material is applied to one or morecomponents of the anode apparatus and/or anode assembly via washing(e.g., painting) the component directly with the material.

In some embodiments, the sealing material is applied to one or morecomponents of the anode apparatus and/or anode assembly via applying thesealing material to the component(s) as a slurry/suspension incombination with a binder or liquid.

In some embodiments, the sealing material is applied to one or more ofthe anode apparatus and the pin via applying/directing the aggregateinto the desired located (e.g. pouring powder, particulate, or pellets),followed by adding the matrix, mechanically agitating/combining, andallowing the sealing material to set/dry.

In some embodiments, the sealing material is applied to one or more ofthe anode apparatus and the pin via spraying.

In some embodiments, the sealing material is applied to one or more ofthe anode apparatus and the pin via gunning.

In some embodiments, the sealing material is applied to one or more ofthe anode apparatus and the pin via slip casting. In some embodiments,the sealing material is applied to one or more of the anode apparatusand the pin via pressure casting. In some embodiments, the sealingmaterial is applied to one or more of the anode apparatus and the pinvia vacuum casting. In some embodiments, the sealing material is appliedto one or more of the anode apparatus and the pin via slurry pressing.In some embodiments, the sealing material is applied to one or more ofthe anode apparatus and the pin via gel casting. In some embodiments,the sealing material is applied to one or more of the anode apparatusand the pin via electrophoretic casting.

In some embodiments, the anode matched aggregate and/or off-gascompatible aggregate is present in mixed form with the sealing material,where the aggregate is from at least 1 vol. % sealing material to notgreater than 99.5 vol. % sealing material.

In some embodiments, the aggregate is present in mixed form with thesealing material, where the aggregate is from at least 1 vol. % sealingmaterial to not greater than 100 vol. % sealing material.

As non-limiting examples, the aggregate comprises: at least 1 vol. %; atleast 5 vol. %; at least 10 vol. %; at least 15 vol. %; at least 20 vol.%; at least 25 vol. %; at least 30 vol. %; at least about 35 vol. %; atleast 40 vol. %; at least 45 vol. %; at least 50 vol. %; at least 55vol. %; at least 60 vol. %; at least 65 vol. %; at least 70 vol. %; atleast 75 vol. %; at least 80 vol. %; at least 85 vol. %; at least 90vol. %; or at least 95 vol. %; or at least 99 vol. % of the sealingmaterial.

As non-limiting examples, the aggregate comprises: not greater than 1vol. %; not greater than 5 vol. %; not greater than 10 vol. %; notgreater than 15 vol. %; not greater than 20 vol. %; not greater than 25vol. %; not greater than 30 vol. %; not greater than about 35 vol. %;not greater than 40 vol. %; not greater than 45 vol. %; not greater than50 vol. %; not greater than 55 vol. %; not greater than 60 vol. %; notgreater than 65 vol. %; not greater than 70 vol. %; not greater than 75vol. %; not greater than 80 vol. %; not greater than 85 vol. %; notgreater than 90 vol. %; or not greater than 95 vol. %; or not greaterthan 99 vol. % of the sealing material.

In some embodiments, a mixture of anode matched aggregate and/or off-gascompatible aggregate and sealing material includes an amount ofaggregate which is sufficient to maintain the ability of the sealingmaterial to adhere components of the anode apparatus (e.g., anode bodyto pin) and/or anode assembly together (e.g., pin to anode support).

In some embodiments, the sealing material is applied to the anode hole(i.e. between the pin and the inner surface of the anode body) in agradient, such that the concentration of sealing material (withanode-matched aggregate and/or off-gas compatible aggregate) varies in aradial direction (i.e. differs from a position adjacent to the pin vs. aposition adjacent to the anode sidewall).

In one embodiment, the gradient is configured such that theconcentration of sealing material is (with anode-matched aggregateand/or off-gas compatible aggregate) higher adjacent to the pin ascompared to adjacent to the inner surface of the anode body.

In one embodiment, the gradient is configured such that theconcentration of sealing material (with anode-matched aggregate and/oroff-gas compatible aggregate) is lower adjacent to the pin as comparedto adjacent to the inner surface of the anode body.

In some embodiments, the sealing material is applied to the anode hole(i.e. between the pin and the inner surface of the anode body) in agradient, such that the concentration of sealing material varies in alateral direction (i.e. differs from a position adjacent to the openingof the hole/upper surface of the anode body as compared to a positionadjacent to the lower end of the anode body).

In one embodiment, the gradient is configured such that theconcentration of sealing material is higher adjacent to the upper end ascompared to adjacent to the lower end of the anode body.

In one embodiment, the gradient is configured such that theconcentration of sealing material is lower adjacent to the upper end ascompared to adjacent to the lower end of the anode body.

In some embodiments, the sealing material is configured with a higherconcentration at a position adjacent to the bath-vapor interface, ascompared to either the upper end (in the vapor phase) or lower end (inthe bath) of the anode body.

In some embodiments, the concentration of sealing material from aposition just below the bath-vapor interface to a position adjacent tothe upper end of the anode is higher than the portion of (anode-matchedaggregate and/or off-gas compatible aggregate in the) sealing materialin the submerged portion of the anode body (e.g. submerged below thebath-vapor interface).

FIGS. 2-15 depict schematic cut-away side view of an exemplary anodeapparatus in accordance with some embodiments of the instant disclosure.FIG. 2 depicts an anode apparatus wherein the sealing material 50 coversa portion of the pin 12 in vapor space 24, the opening 32 and an entiretop surface of the anode body 30. FIG. 3 depicts an anode apparatuswherein the sealing material 50 covers an entirety of the pin 12 invapor space 24, the opening 32 and a portion of the top surface of theanode body 30. FIG. 4 depicts an anode apparatus wherein the sealingmaterial 50 covers a portion of the pin 12 in vapor space 24, theopening 32, and a portion of the top surface of the anode body 30. FIG.5 depicts an anode apparatus wherein the sealing material 50 covers anentirety of the pin 12 above the top surface of the anode body 30 (i.e.within the vapor space 24 and refractory portion 18), the opening 32,and a portion of the top surface of the anode body 30.

FIG. 6 depicts an anode apparatus wherein the sealing material 50 coversan entirety of the pin 12 in vapor space 24, the opening 32 and anentire top surface of the anode body 30. In FIG. 6, the sealing material50 extends beyond a peripheral edge of the top surface of the anode bodyand covers a portion of the sidewall 40 of the anode body 30. FIG. 7depicts an anode apparatus wherein the sealing material 50 covers aportion of the pin 12 in vapor space 24, the opening 32, and an entiretop surface of the anode body 30. In FIG. 7, the sealing material 50extends beyond a peripheral edge of the top surface of the anode bodyand covers a portion of the sidewall 40 of the anode body 30.

FIG. 8 depicts an anode apparatus wherein the sealing material 50 coversan entirety of the pin 12 in vapor space 24. The sealing material 50covers opening 32 and an entire top surface of the anode body 30. Thesealing material 50 extends beyond a peripheral edge of the top surfaceof the anode body and covers a portion of the sidewall 40 of the anodebody 30. Sealing material 50 is also disposed between the vapor space 24and the refractory 18 to prevent corrosive chemicals from corrodingexposed portions of the pin 12 (i.e. not covered by sealing material50).

FIG. 9 depicts an anode apparatus wherein the sealing material 50 coversa portion of the pin 12 in vapor space 24, the opening 32, and an entiretop surface of the anode body 30. The sealing material 50 extends beyonda peripheral edge of the top surface of the anode body and covers aportion of the sidewall 40 of the anode body 30. A portion of the pin 12in the vapor phase 24 is not covered by sealing material 50. Sealingmaterial 50 is also disposed between the vapor space 24 and therefractory 18 to prevent corrosive chemicals from corroding exposedportions of the pin 12 in the refractory 18.

FIG. 10 depicts an anode apparatus wherein the sealing material 50covers an entirety of the pin 12 in vapor space 24. The sealing material50 covers opening 32 and an entire top surface of the anode body 30. Thesealing material 50 does not extend beyond a peripheral edge of the topsurface of the anode body to cover a portion of the sidewall 40 of theanode body 30. Sealing material 50 is also disposed between the vaporspace 24 and the refractory 18 to prevent corrosive chemicals fromcorroding exposed portions of the pin 12 (i.e. not covered by sealingmaterial 50).

FIG. 11 depicts an anode apparatus wherein the sealing material 50covers a portion of the pin 12 in vapor space 24, the opening 32, and anentire top surface of the anode body 30. The sealing material 50 extendsbeyond a peripheral edge of the top surface of the anode body and coversa portion of the sidewall 40 of the anode body 30. The sealing materialextends down the sidewall 40 of the anode body 30 proximate to theinterface 22.

FIG. 12 depicts an anode apparatus wherein the sealing material 50covers a portion of the pin 12 in vapor space 24, the opening 32 and anentire top surface of the anode body 30.

FIG. 13 depict an anode apparatus wherein the sealing material 50 coversa portion of the pin 12 in vapor space 24, the opening 32 and an entiretop surface of the anode body 30. The sealing material is also disposedwithin the hole 34 to cover a portion of the pin 12 within the anodebody 30. The sealing material 50 covers a portion of the pin 12 withinthe anode body 30 that is above the interface 22.

FIG. 14 depicts an anode apparatus wherein the sealing material 50 isdisposed within the hole 34 to cover a portion of the pin 12 within theanode body 30. The sealing material 50 covers a portion of the pin 12within the anode body 30 that is above the interface 22.

FIG. 15 depicts an anode apparatus wherein the sealing material 50 isdisposed within the hole 34 to cover a portion of the pin 12 within theanode body 30. The sealing material 50 covers a portion of the pin 12within the anode body 30 that is above the interface 22. A fillermaterial is disposed within the hole 34 below the sealing material 50.

Reference will now be made in detail to prophetic examples, which (incombination with the accompanying drawings and previous descriptionsthereof) at least partially assist in illustrating various pertinentembodiments of the present invention.

Example: Prophetic Anode Manufacture

Non-limiting examples of producing the anode body include: presssintering, fuse casting, and casting, which is disclosed incorresponding U.S. Pat. No. 7,235,161, which contents are incorporatedby reference herein by their entirety.

Once the anode body is formed, the pin and filler materials, if beingused, are incorporated into the anode body. For example, if a filler(e.g. conductive filler) is utilized, the pin is placed in the hole ofthe anode body and filler (e.g. in the form of particulate material) isinserted into the void between the pin and the inner surface of the holein the anode body. Then the sealing material (i.e., in order to providea mechanical attachment and/or seal the pin and/or filler material intothe hole in the anode body), is added to the upper end of the anodebody. In some embodiments, the sealing material is configured to extendat least partially into the hole in the anode body. In some embodiments,the sealing material is configured to sit on top of the anode body,proximal to the upper end of the hole, and surrounding the pin as itextends upward from the anode body. In some embodiments, the sealingmaterial is placed on top of the anode body in a position surroundingthe pin.

In some embodiments, the sealing material is configured to extend aportion of the way into the hole at the upper end of the anode. In someembodiments, the sealing material is configured to cover the top portionof the anode body. In some embodiments, the sealing material isconfigured to contact at least a portion of the outer perimetricalsidewall of the anode body. In some embodiments, the sealing material isconfigured to contact the pin, the inner portion of the anode body(hole), the upper portion/top surface of the anode body, and the upperportion of at least a portion of the outside perimetrical wall of theanode body.

While various embodiments of the present invention have been describedin detail, it is apparent that modifications and adaptations of thoseembodiments will occur to those skilled in the art. However, it is to beexpressly understood that such modifications and adaptations are withinthe spirit and scope of the present invention.

Prophetic Comparative Example

Two anode assemblies (AA1=prior art and AA2=an embodiment in accordancewith the instant disclosure) are made with: the same anode bodydimensions and composition in accordance with that set out indisclosures of U.S. Pat. Nos. 7,507,322 and 7,235,161; the same pinmaterial (copper or copper alloy); and different sealing materials.

In AA1 the first instance (prior art), the sealing material is inaccordance with the disclosure of U.S. Pat. No. 7,169,270. In the secondinstance (instant disclosure), the sealing material has 5 wt. % to 100wt. % the sealing material is a castable ceramic or cermet containingAl₂O₃, SiO₂, MgO, CaO, Na₂O, and combinations thereof, where at leastsome of the silicate and/or aluminate aggregates in the sealing material(e.g. castable ceramic) are replaced with a magnetite aggregate (e.g.anode-matched/anode compatible aggregate), configured with comparablesizing as the aggregate appropriate sizing as the aggregate in the priorart run.

Both anode assemblies are configured as the embodiment shown in FIG. 2.Both anode assemblies were incorporated into an aluminum electrolysiscell and operated as electrodes (anodes) extending across the bath-vaporinterface for a sufficient length of time in order to evaluate whetherany reactions occur as a result of the interaction of the reactivespecies present in the vapor space of the cell with the sealing materialand/or components thereof.

Anode assemblies are pulled out of the cell and evaluated in order toevaluate and/or quantify corrosion on the various anode apparatuscomponents (e.g. sealing material). It will be found that the sealingmaterial of AA2, i.e. sealing material with aggregate tailored (i.e.matched) to the anode body, performed better (exhibits less corrosion)than the prior art sealing material. Also, it will be found that the pinof AA2 performed better (exhibits less corrosion) than the pin of AA1(the prior art anode apparatus).

Without being bound by a particular mechanism or theory, it is believedthat during cell operating conditions (i.e. at elevated temperature andin a corrosive environment in the vapor space, which contains reactivefluoride gas, oxygen gas, and/or other reactive vapor species), thesilica (e.g. SiO₂ present as aggregate in the sealing material) createspockets of reactive silicates available to interact with the reactivespecies present in the vapor space.

Without being bound by a particular mechanism or theory, it is believedthat the reactive silicates in the aggregates of the sealing material(i.e. AA1) will react with fluoride gas present in the vapor space ofthe cell, in turn creating silicon tetrafluoride, which is in turncorrosive to the pin. Without being bound by a particular mechanism ortheory, it is believed that as the reactive silicon fluoride speciesfurther interacts/reacts with the pin, pockets or holes are created inthe sealing material (i.e. reducing the mechanical strength/structuralsupport of the sealing material, and yielding pores/holes where thereactive species can further penetrate into and react with the sealingmaterial, or other components of the anode apparatus. Without beingbound by a particular mechanism or theory, as the silicon fluoridespecies react with the pin materials, initiation sites of corrosionoccur on the pin and the structural integrity of the anode apparatusand/or the electrical efficiency of this component are further reduced).

Without being bound by a particular mechanism or theory, it is believedthat during cell operating conditions (i.e. at elevated temperature andin a corrosive environment in the vapor space, which contains reactivefluoride gas, oxygen gas, and/or other reactive vapor species), themagnetite aggregate (e.g. SiO₂ and/or Al₂O₃ replacement in the sealingmaterial) creates pockets of aggregate tailored to not undergosignificant reactions with the reactive species (and thus, will not formpores in the sealing material and/or further attribute to pincorrosion).

Without being bound by a particular mechanism or theory, it is believedthat the reactive silicates in the aggregates of the sealing material(i.e. AA1) will react with fluoride gas present in the vapor space ofthe cell, in turn creating silicon tetrafluoride, which is in turncorrosive to the pin.

Various ones of the inventive aspects noted hereinabove may be combinedto yield inert anode apparatuses having a pin which provides amechanical and electrical connection to the anode body, where the pinextends down into the hole of the anode body and is positioned such thatthe lower end of the pin is located above the vapor-bath interface.

These and other aspects, advantages, and novel features of the inventionare set forth in part in the description that follows and will becomeapparent to those skilled in the art upon examination of the followingdescription and figures, or may be learned by practicing the invention.

REFERENCE NUMBERS

-   Anode Assembly 10-   Pin 12-   First end 14-   Second end 16-   Anode support 18-   Current supply 20-   Bath-vapor interface 22-   Vapor space 24-   Bath 26-   Anode apparatus 28-   Anode body 30-   Upper opening 32-   Anode inner sidewall (defining the hole) 34-   Upper end of anode 36-   Lower end of anode 38-   Anode outer sidewall 40-   Conductive filler 42-   Particulate (conductive filler) material 44-   Liquid/Slurry (conductive filler) material 46-   Top surface of anode 48-   Sealing material 50-   Aggregate 52 (large and/or small fines, e.g., aggregate particulate,    powder)-   Matrix/Binder material 54

We claim:
 1. An anode assembly, comprising: an anode support; and ananode apparatus mechanically attached to the anode support, wherein theanode apparatus comprises: (a) an anode body comprising at least oneouter sidewall, wherein the outer sidewall is configured to define ashape of the anode body, and to perimetrically surround a hole in theanode body, wherein the hole comprises an upper opening in a top surfaceof the anode body and wherein the hole axially extends into the anodebody; (b) a pin comprising: a. a first end connected to a currentsupply, and b. a second end opposite the first end, wherein the secondend extends downward into the upper end of the anode body and into thehole of the anode body; and (c) a sealing material comprising anaggregate and a matrix, wherein the sealing material is configured tocover at least a portion of at least one of the following: (1) an innersidewall of the anode body; (2) the top surface of the anode body; (3)the pin; and (4) the anode support.
 2. The anode assembly of claim 1,wherein the sealing material comprises at least one of: water, polymers,organics, dispersants, or diluents.
 3. The anode assembly of claim 1,wherein a sealing material is configured to cover at least a portion ofat least one of the following: (1) an inner sidewall of the anode body;(2) the pin; and (3) a filler material.
 4. The anode apparatus of claim1, wherein, the first end of the pin is configured to be retained withinan anode support.
 5. The anode apparatus of claim 1, wherein the filleris retained in the hole between the inner sidewall of the anode body andthe pin.
 6. The anode apparatus of claim 1, wherein the sealing materialis configured to enclose the conductive filler into the anode bodybetween the inner sidewall of the anode body and the pin.
 7. The anodeapparatus of claim 1, wherein the sealing material is cast in place. 8.The anode apparatus of claim 1, wherein the sealing material is pre-castand screwed into the anode body.
 9. The anode apparatus of claim 1,wherein the sealing material is sintered into place during the sinteringof the green form anode body into the final anode body.
 10. The anodeapparatus of claim 1, wherein the sealing material is retained above thetop surface of the anode body.
 11. The anode apparatus of claim 1,wherein the sealing material is retained in the hole.
 12. The anodeapparatus of claim 10, wherein above the top surface of the anode bodyincludes extending along the pin.
 13. The anode apparatus of claim 10,wherein above the top surface of the anode body includes extending alongthe pin and into the anode support.
 14. The anode apparatus of claim 10,wherein above the top surface includes extending across the top surfaceof the upper portion of the anode body.
 15. The anode apparatus of claim10, wherein above the top surface includes extending across the topsurface and extending down around the outer sidewall of the anode body.16. The anode apparatus of claim 1, wherein the sealing material isapplied to the anode hole between the pin and the inner surface of theanode body in a gradient, such that the concentration of sealingmaterial varies in a radial direction.
 17. The anode apparatus of claim16, wherein the gradient is configured such that the concentration ofsealing material is higher adjacent to the pin as compared to adjacentto the inner surface of the anode body.
 18. The anode apparatus of claim16, wherein the gradient is configured such that the concentration ofsealing material is lower adjacent to the pin as compared to adjacent tothe inner surface of the anode body.
 19. The anode apparatus of claim 1,wherein the sealing material is applied to the anode hole between thepin and the inner surface of the anode body in a gradient, such that theconcentration of sealing material varies in a lateral direction.
 20. Theanode apparatus of claim 19, wherein the gradient is configured suchthat the concentration of sealing material is higher adjacent to theupper end as compared to adjacent to the lower end of the anode body.21. The anode apparatus of claim 19, wherein the gradient is configuredsuch that the concentration of sealing material is lower adjacent to theupper end as compared to adjacent to the lower end of the anode body.22. The anode apparatus of claim 19, wherein the sealing material isconfigured with a higher concentration at a position adjacent to thebath-vapor interface, as compared to either the upper end in the vaporphase or the lower end in the bath of the anode body.
 23. The anodeapparatus of claim 19, wherein the concentration of sealing materialfrom a position just below the bath-vapor interface to a positionadjacent to the upper end of the anode is higher than the portion ofsealing material in the submerged portion of the anode body.
 24. Anelectrolysis cell, comprising: a cell structure comprising a cell bottomand a cell sidewall, wherein the cell sidewall is configured toperimetrically surround the cell bottom and extend in an upwarddirection from the cell bottom to define a control volume, wherein thecontrol volume is configured to retain a molten electrolyte bath; and ananode assembly configured to direct current into the molten electrolytebath, wherein the anode assembly comprises: an anode support; and ananode apparatus mechanically attached to the anode support, wherein theanode apparatus comprises: (a) an anode body comprising at least oneouter sidewall, wherein the outer sidewall is configured to define theanode shape and to perimetrically surround a hole in the anode body,wherein the hole comprises an upper opening in the top of the anode bodyand wherein the hole axially extends into the anode body; and (b) an pincomprising: a first end connected to a current supply, and a second endopposite the first end, wherein the second end is configured to extenddown into the upper end of the anode body and into the hole of the anodebody; and (c) a sealing material configured to cover at least a portionof at least one of the following: an inner sidewall of the anode body;the top surface of the anode body; the pin; and the anode support.